Right now, dramatic testimony in the Florida murder trial that began with a fight over loud music. Michael Dunn is charged with shooting an unarmed teen ager and his fiance took the stand as a witness for the prosecution. Ryan Owens has the latest. What did the defendant say? Oh, I hate that thug music. Those are the last words she said she heard Michael Dunn say the night he opened fire on an SUV full of teen agers. Killing one of them allegedly over loud rap music. Rhonda Royer crying and shaking uncontrollably said she got out of Dunn's car and walked into this Jacksonville, Florida, gas station. That's her at the counter when she heard gunshots. Oh, my god, somebody is shooting. I heard pop, pop, pop. Reporter: She says she ran outside and Dunn told her to get back if the car. Did you see a firearm at that point in time? Yes, Michael was putting it into the glove box. Reporter: She told the jury that Michael Dunn had three or four cocktails at his son's wedding before they stopped at the store for a bottle of wine that November night in 2012. Prosecutors say he fired ten times, murdering 17-year-old Jordan Davis. Like individual lvigilantism. Reporter: After this, they went back to their hotel room and ordered pizza. Royer testified it was her idea to go back to the hotel room withoutng anybody what happened. Why did you decide you needed to go home? Because I thought I was going to be arrested, too. Reporter: Dunn has pleaded not guilty and maintains it was self-defense under Florida's controversial stand your ground law. Here's what Dunn told investigators after he was arrested, even though there were no weapons found in the car. It was a barrel or a stick, but sir -- they're -- they're like, we're gonna kill you. Reporter: For "Good morning America," Ryan Owens, ABC news, Jacksonville, Florida.

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